In a generally used switchgear, the structure of a state display device which mechanically displays the opening/closing state and the number of opening/closing times of a contact is configured, for example, as shown in FIG. 9 and FIG. 10. More specifically, the state display device includes: an ON/OFF display plate 7 which is provided with a display of “ON”/“OFF” on each of two different angle faces, and displays the opening/closing state of the contact by mechanically rotating; and, similarly, a mechanical operation counter 12 which counts and displays the number of opening/closing times by rotation of a driving lever 13. Both of the ON/OFF display plate 7 and the operation counter 12 face a front cover 18 of the switchgear and are arranged so as to be able to confirm the state display from the front of the switchgear through a display window 19 provided on the front cover 18.
The ON/OFF display plate 7 and the operation counter 12 are coupled to a main shaft of the switchgear via a movable plate 5 and a tension spring 14; and the ON/OFF display plate 7 and the driving lever 13 of the operation counter 12 are rotated in response to the opening/closing operation of the contact to switch the display of “ON”/“OFF” and to count the number of opening/closing times. Such a state display device is also disclosed in Japanese Unexamined Utility Model Publication No. H4-124726 (Patent Document 1).
Furthermore, as other example, in order to electrically input/output information to a control device, there is also an example in which a display device equipped with a cathode ray tube (CRT) and a keyboard is attached with inclined upward so that a worker operates easily (for example, see Patent Document 2).